﻿// Production steps of ECMA-262, Edition 5, 15.4.4.19
// Reference: http://es5.github.com/#x15.4.4.19
if (!Array.prototype.map) {
    Array.prototype.map = function (callback, thisArg) {

        var T, A, k;

        if (this == null) {
            throw new TypeError(" this is null or not defined");
        }

        // 1. Let O be the result of calling ToObject passing the |this| value as the argument.
        var O = Object(this);

        // 2. Let lenValue be the result of calling the Get internal method of O with the 
        //    argument "length".
        // 3. Let len be ToUint32(lenValue).
        var len = O.length >>> 0;

        // 4. If IsCallable(callback) is false, throw a TypeError exception.
        // See: http://es5.github.com/#x9.11
        if (typeof callback !== "function") {
            throw new TypeError(callback + " is not a function");
        }

        // 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
        if (arguments.length > 1) {
            T = thisArg;
        }

        // 6. Let A be a new array created as if by the expression new Array(len) where
        //    Array is the standard built-in constructor with that name and len is the 
        //    value of len.
        A = new Array(len);

        // 7. Let k be 0
        k = 0;

        // 8. Repeat, while k < len
        while (k < len) {

            var kValue, mappedValue;

            // a. Let Pk be ToString(k).
            //   This is implicit for LHS operands of the in operator
            // b. Let kPresent be the result of calling the HasProperty 
            //   internal method of O with argument Pk.
            //   This step can be combined with c
            // c. If kPresent is true, then
            if (k in O) {

                // i. Let kValue be the result of calling the Get internal
                //    method of O with argument Pk.
                kValue = O[k];

                // ii. Let mappedValue be the result of calling the Call 
                //     internal method of callback with T as the this value and 
                //     argument list containing kValue, k, and O.
                mappedValue = callback.call(T, kValue, k, O);

                // iii. Call the DefineOwnProperty internal method of A with arguments
                //      Pk, Property Descriptor {Value: mappedValue, : true, 
                //      Enumerable: true, Configurable: true}, and false.

                // In browsers that support Object.defineProperty, use the following:
                // Object.defineProperty(A, Pk, { value: mappedValue, writable: true, 
                // enumerable: true, configurable: true });

                // For best browser support, use the following:
                A[k] = mappedValue;
            }
            // d. Increase k by 1.
            k++;
        }

        // 9. return A
        return A;
    };
}


if (!Array.prototype.indexOf) {
    Array.prototype.indexOf = function (searchElement, fromIndex) {
        var i,
            pivot = (fromIndex) ? fromIndex : 0,
            length;

        if (!this) {
            throw new TypeError();
        }

        length = this.length;

        if (length === 0 || pivot >= length) {
            return -1;
        }

        if (pivot < 0) {
            pivot = length - Math.abs(pivot);
        }

        for (i = pivot; i < length; i++) {
            if (this[i] === searchElement) {
                return i;
            }
        }
        return -1;
    };
}

if (!Array.prototype.forEach) {
    Array.prototype.forEach = function (fn, scope) {
        'use strict';
        var i, len;
        for (i = 0, len = this.length; i < len; ++i) {
            if (i in this) {
                fn.call(scope, this[i], i, this);
            }
        }
    };
}

if ('function' !== typeof Array.prototype.reduce) {
    Array.prototype.reduce = function (callback, opt_initialValue) {
        'use strict';
        if (null === this || 'undefined' === typeof this) {
            // At the moment all modern browsers, that support strict mode, have
            // native implementation of Array.prototype.reduce. For instance, IE8
            // does not support strict mode, so this check is actually useless.
            throw new TypeError(
                'Array.prototype.reduce called on null or undefined');
        }
        if ('function' !== typeof callback) {
            throw new TypeError(callback + ' is not a function');
        }
        var index, value,
            length = this.length >>> 0,
            isValueSet = false;
        if (1 < arguments.length) {
            value = opt_initialValue;
            isValueSet = true;
        }
        for (index = 0; length > index; ++index) {
            if (this.hasOwnProperty(index)) {
                if (isValueSet) {
                    value = callback(value, this[index], index, this);
                }
                else {
                    value = this[index];
                    isValueSet = true;
                }
            }
        }
        if (!isValueSet) {
            throw new TypeError('Reduce of empty array with no initial value');
        }
        return value;
    };
}

if (!Array.prototype.filter) {
    Array.prototype.filter = function (fun /*, thisp */) {
        "use strict";

        if (this == null)
            throw new TypeError();

        var t = Object(this);
        var len = t.length >>> 0;
        if (typeof fun != "function")
            throw new TypeError();

        var res = [];
        var thisp = arguments[1];
        for (var i = 0; i < len; i++) {
            if (i in t) {
                var val = t[i]; // in case fun mutates this
                if (fun.call(thisp, val, i, t))
                    res.push(val);
            }
        }

        return res;
    };
}

if (!String.prototype.trim) {
    String.prototype.trim = function () {
        return this.replace(/^\s+|\s+$/gm, '');
    };
}

if (!Date.now) {
    Date.now = function now() {
        return new Date().getTime();
    };
}